UK butterfly numbers hit hard

Scientists are warning that another wet summer following two years of wash-outs could drive some UK butterfly species to extinction, the Telegraph reports.

A survey by the UK Butterfly Monitoring Scheme, which began recording populations in 1976, showed that 12 species last year "suffered the worst summer on record".

Overall, butterflies endured the "second-worst summer" since 1981, and if 2009 offers similar weather, it could be the end for the rare high brown fritillary, pearl-bordered fritillary and wood white. Also, the relatively common orange-tip and small tortoiseshell might become an "increasingly rare sight".

Dr Tom Brereton, head of monitoring for Butterfly Conservation, explained: "If we have a nice sunny year with only bouts of rain some species will bounce back, but some species got to such a low ebb on some sites we're not sure if it has tipped them over the edge of extinction. A lot of sites are quite isolated, and when they go, it's not easy for them to get recolonised."

The survey's gloomy findings also showed that "formerly common species" including the small copper and small heath have "declined in the past few decades".

Butterfly populations are not just threatened by Britain's run of atrocious summers; habitats face destruction by development and intensive agriculture while climate change could prove tricky for some species.

Dr Brereton said: "Climate change will be a huge factor in the future. Pretty much most butterflies' distribution will change. That's fine for the more mobile, commoner species but a lot of our threatened species won't be able to move to other parts of the country that might become suitable for them."

The government, meanwhile, has promised action. Wildlife minister Huw Irranca-Davies said: "Climate change is having a detrimental effect on a number of our butterfly species and in parts of England we're in danger of losing some species altogether. Butterflies need good habitats to thrive and the Government will continue to support schemes to promote the recovery of butterfly numbers." ®